Hello Zuscic Pavel
If a Global Reader doesn't see all subscriptions in a tenant, it could be due to one of the following reasons:
The Global Reader doesn't have access to the subscriptions: To view all subscriptions in a tenant, a Global Reader must have access to the subscriptions. You can grant access to the Global Reader by assigning the appropriate role to the Global Reader at the subscription level.
The Global Reader is only able to see subscriptions in a specific directory: If the Global Reader is only able to see subscriptions in a specific directory, you can change the default directory by following these steps:
- Go to the Azure portal, in the default subscription filter section, select the appropriate directory and subscription.
- If you have been granted access to one or more resource groups, rather than to an entire subscription, select the subscription to which that resource group belongs.[0] You'll then work in the context of that subscription, but will only be able to access the designated resource group(s).
- The Global Reader is only able to see subscriptions in a specific management group: If the Global Reader is only able to see subscriptions in a specific management group, you can change the default management group by following these steps:
- Go to the Azure portal.
- In the Default subscription filter section, select the appropriate management group and subscription
- If you have been granted access to one or more resource groups, rather than to an entire subscription, select the subscription to which that resource group belongs. You'll then work in the context of that management group, but will only be able to access the designated resource group(s).
https://learn.microsoft.com/en-us/azure/azure-portal/set-preferences#subscription-filters
https://azure.microsoft.com/en-us/updates/updates-to-subscription-filtering/
Let me know if you need more help with this.
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